The fad diet experts warn of life-threatening risks

Bentonite clay rocketed to fame when starlet Shailene Woodley said she eats it to detox her body. But she's not the first one to try clay as a dietary supplement. It's been marketed as a detoxifier, a face mask, a constipation aid, an immune system booster and even a weight loss tool. (Lesser known use: It's the main ingredient in most cat litters.) It's that last one that has experts worried.

Women around the world are drinking clay mixtures or taking clay tablets in an effort to lose weight. The properties that make it great cat litter are also what makes it effective for losing weight. Since the clay is so absorbent, it sucks up water and expands in your stomach making you feel full. Reports of losing 10 pounds in one week thrill dieters but set public health experts on edge. Their main concern is that since you are eating, well, dirt, that you could be ingesting high levels of arsenic and lead. Some clay isn't contaminated but some is, and since the FDA does not regulate supplements, you can't know what exactly you are swallowing.

In addition to being absorbent, it turns out that clay is good at ridding the body of things but it works on the good stuff as well as the bad, said Dr. Anton Emmanuel, M.D., a gastroenterologist at University College Hospital, London, in an interview with the Daily Mail. "The clay acts as a resin and binds everything — good and bad — making it harder for the body to digest vital nutrients such as iron and calcium."

According to Emmanuel, there are also reports of clay ingestion causing bowel perforations — which require surgery — and even kidney and heart failure, as it can disrupt potassium levels in the body. He adds that any dramatic changes in weight will only be short term.

Yet that hasn't slowed down sales. Clay is one of the fastest growing supplements as more and more people jump on the train looking for a quick fix. One woman even told the Daily Mail that she plans on doing the clay cleanse every year after the holidays. "It gives me a licence to indulge over Christmas, as I know I can easily get the weight off again."

This idea of easy-on easy-off doesn't thrill nutritionists either who point out that regardless of what is in the clay, using it this way only leads to yo-yo dieting and all the frustration that comes with it instead of teaching people how to make healthier choices.

I remember growing up and hearing rumors of models eating cotton balls or toilet paper in order to blunt their hunger but now kitty litter? Perhaps we should be putting these energies into finding out why people feel like taking such drastic measures is worth the risk.